1. Field of the Invention
The present invention relates to a backlight assembly and an LCD (Liquid Crystal Display) apparatus, and more particularly to a backlight assembly for reducing a whole size thereof and improving a light efficiency and an LCD apparatus having the same.
2. Description of the Related Art
In general, an LCD apparatus includes a backlight assembly for generating light and an LCD panel for displaying an image in response to the light provided from the backlight assembly.
However, a backlight assembly has a higher power consumption and an LCD apparatus has an increased weight and an enlarged size due to the backlight assembly.
Recently, a point light source, for example such as a light-emitting diode, is used as a lamp in a backlight assembly. The light-emitting diode has a lower power consumption and a size suitable for applying to the backlight assembly. However, since the light-emitting diode cannot irradiate light to a long distant place, a light-emitting diode is mainly applied to a mobile LCD apparatus for medium and small size products having a small display screen.
FIG. 1 is a cross-sectional view showing a backlight assembly of a conventional LCD apparatus.
Referring to FIG. 1, a backlight assembly 50 includes a light source 10 for generating light and a light guide plate 20 for guiding the light and emitting the light in a predetermined direction.
The light guide plate 20 includes an incident surface 21 for receiving the light emitted from the light source 10, a reflecting surface 22 for reflecting the light incident through the incident surface 21, that is extended from a first end of the incident surface 21, and an emitting surface 23 for emitting the light incident through the incident surface 21, that is extended from a second end of the incident surface 21 and parallel to the reflecting surface 22.
As shown in FIG. 1, since the reflecting surface 22 and the emitting surface 23 are parallel to each other, a height “h” of the incident surface 21 is same to a linear distance “d” line between the reflecting surface 22 and the emitting surface 23.
The backlight assembly 50 further includes a plurality of optical sheets 30 disposed on the emitting surface 23 and a reflecting plate 40 disposed under the reflecting surface 22.
The height “h” of the incident surface 21 of the light guide plate 20 depends upon the light source 10. That is, the height “h” of the incident surface 21 increases according as a size of the light source 10 increases, so that the linear distance “d” between the reflecting surface 22 and the emitting surface 23 increases. Thus, an entire thickness “t” of the backlight assembly 50 increases.
However, when a thickness of the light guide plate 20 decreases in order to reduce the entire thickness “t” of the backlight assembly 50, the height “h” of the incident surface 21 decreases with the reduction of the entire thickness “t” of the backlight assembly 50. As a result, a light efficiency of the backlight assembly 50 may be deteriorated.